Improvement in slate-frame attachments



No. 204,740. Patented June11,187s.

N. PETERS. PHOTO-LITHOGRIPMER. WASHINGTON, D. C.

UNITED STATES PATENT OEEIoE.

FRANK' G. JOHNSON, OF'NEW YORK, N. Y.

IMPROVEMENT IN SLATE-FRAME ATTACHMENTS.`

Specification forming part of Letters Patent No. 204,740, dated June l1, 1878; application filed November 9, 1877.

To all whom it may concern:

Be it known that I, FRANK G. JOHNSON, of the city, county, and State of New York, have invented a new and useful Improvement in Slates; and I do hereby decla-re that the following is a full, clear, and exact description ot' the construction and operation of the same, reference being had to the accompanyin g drawings, making a part of this specification, in whichy Figure 1 is a view seen by looking at the face of the slate, and Fig. 2 a vertical section cut thro-ugh the line a' a: in Fig. 1.

Like letters refer to like parts.

The nature and object of my invention are to provide an eraser for rubbing out marks from the slate, the eraser being attached to the slate in such a manner that it is securely held to the same when notin use, and yet rendered easily and quickly detachable when it is required for use, and as easily and quickly replaced after it has been used, the whole being so arranged upon the slate as not to project above or outside of the slate-frame, to prevent interference with the carrying or packing of the slate.

To enable others to make and use my invention, l proceed to more minutely describe its construction and operations.

A represents the slate, including the frame. B represents the eraser, which consists of a thin square or other shaped piece of wood or suitable substance, having glued on the under side of it a piece of suitable fibrous fabric or chamois, b, and on the upper side a circular depression, b. This depression, by receiving the thumb or finger, serves to assist in drawing the eraser from under the fastening C, in rubbing it over the face of the slate, and in replacing it under the fastening, all three of which performances may be accomplished with one hand without even raising the eraser from the face of the slate.

The eraser, when not in use, is securely held to the slate by means of a strip of spring metal, G, sunk flush into one corner of the slateframe, and securely fastened thereto by having its outer'end screwed or riveted to the frame, as shown at d. The other end of the metallic strip O projects inward beyond the frame and over the face of the slate, and suiciently above the face of the slate to allow the eraser to be pushed in between the metallic strip and face of the slate. On the under side of the inner or free end of the metallic strip is a rounded projection, c, which falls or springs into the circular depression b 'on the upper side of the eraser. The metallic strip O, by its elasticity, and the rounded projection c, will rise and fall sufficiently to allow the eraser to be pushed under it and drawn out from under it without otherwise lifting the strip, by which means the eraser can be quickly and easily disengaged and replaced with one hand. The length of the metallic strip O, being just sufficient to cause the projection c to fall into the depression b, securely holds the eraser tight in the corner of the slateTframe.

What I claim as my invention, and desire to secure by Letters Patent, is y 1. The slate A, the frame of which is provided at its inner edge with a spring-strip, O, arranged to project over the face ofthe slate, and adapted to hold the eraser B, substantially as described.

2. The slate A, the frame of which has secured at its inner edge a spring-strip, C, having the rounded depression c, in combination with the eraser B, provided with the circular.

depression b, all constructed and arranged to operate as set forth.

FRANK G. JOHNSON.,

Witnesses WM. HANNAM, 0. R. WARE. 

